Core assembly method

ABSTRACT

Assembling within tubular cores tubular core tips of the type having a cylindrical wall and, at one axial end thereof, a radially-inwardly extending entrance flange by introducing the tip, entrance flange end first, into the core and then, simultaneously, expanding the entrance flange radially outwardly into the core and shearing portions of the tip wall and forcing the sheared portions outwardly into the core.

[151 3,657,797 51 Apr. 25, 1972 United States Patent 7 Robinson References Cited [54] CORE ASSEMBLY METHOD UNITED STATES PATENTS [72] lnventor: Walter B. Robinson, Natick, Mass.

Pattle Primary Examiner-Charlie T. Moon Attorney-Martin Kirkpatrick [22] Filed:

[21] Appl. No.: 1,825

Related U.S. Application Data ABSTRACT Assembling within tubular cores tubular core tips of the type having a cylindrical wall and, at one axial end ally-inwardly extending entrance flan 0e pe m mm re g mmwm Fu TC onmam md eunmd hde n t a m w .In a V. M .0 3D. 6 fi 8 6e h t entrance flange end first, into the core and th ously, expanding the entrance flan m .LQW JA a 2 b 531 5 3 /410 9 2 2/P, am 93 222 9 1. B39 1 5 H2 I 9 u. m J x 2 m2 m 3 U 4 5 J "2 9 2. m3 w m Mm 6 m2 4 n" 6 m a m N mm mm S 1m n .a O "HM n h .md 0 Lo .w d .wm S Lfl i Dd U hF .l. 1.1 2 2 8 6 5 55 1 l. .11

the core and shearing portions of sheared portions outwardly into th B COTE.

10 Claims, 6 Drawing Figures PATEHTED APR 2 5 1912 SHEET 2 OF 3 FIG 5 CORE ASSEMBLY METHOD The present application is a division of copending application Ser. No. 646,599, filed June 16, 1967, now US. Pat. No. 3,512,240.

This invention relates to placing core tips within the ends of cores and securing them in place.

It is a primary object of the present invention to provide a new and improved method for assembling within tubular cores, core tips of the type having at one axial end thereof a radially-inwardly extending entrance flange. Other objects include providing a method for fixing core tips more tightly and accurately than heretofore possible in a configuration that provides for unobstructed passage of a mandrel through the core.

The invention accomplishes these and other objects by introducing a core tip, the end thereof including the entrance flange first, into the core coaxially therewith and, simultaneously, expanding the entrance flange radially outwardly into the core wall, and shearing portions of the tip wall and forcing the sheared portions radially outwardly into the core wall.

Other objects, features and advantages will appear from the following detailed description of a preferred manner of practicing the invention, taken together with the attached drawings in which:

FIG. 1 is a perspective view of a core assembly tool useful in practicing the present invention, together with a core tip useful therewith;

FIGS. 2-4 are plan sectional views of the tool of FIG. 1; and

FIGS. 5-6 are perspective views of components of the tool of FIG. 1.

Referring more particularly to the drawings, there is shown in FIG. 1 a core tip assembly tool mounted on an air cylinder 12 for forcing a generally tubular metal core tip 14 into the end of a tubular paper core 16 and securing it in place within the core. Core tip 14 includes a generally cylindrical wall 18 having an outside diameter substantially equal to the inside diameter of core 16 to provide a tight fit between the two, a radially-outwardly extending, circumferential reinforcing flange 20 at one axial end of wall 18, and an inwardly inclined flange or core entrance portion 22 at the other axial end of wall 18. Flange 20 extends perpendicular to the axis of the core tip for engaging the axial end of core 16; flange 22 (as shown in axial cross-section in FIGS. 3-4) provides an entrance radius for guiding core tip 14 into core 16 and preventing galling of the interior surface of core 16 during tip insertion. A keyway 24 with axially-extending sides is provided in flange 20 for engaging a corresponding driving notch or keyway 26 in the end portion of tube 16.

As shown more clearly in FIGS. 2-4, assembly tool 10 comprises a substantially cylindrical housing 30 with a radially-extending base plate 32 at the bottom thereof, an operating shaft 34 extending axially through housing 30, and a segmented expansion head 36 mounted on top of housing 30. The diameter of housing 30 is slightly less than the inside diameter of wall 18 of core tip 14; base plate 32 has a diameter greater than that of core 16 or flange 20 of core tip 14; and the diameter of the portion of head 36 having the greatest diameter when the head is in its unexpanded position shown in FIG. 1 is approximately equal to that of housing 30 and, preferably, slightly greater than the minimum diameter of entrance flange 22 of core tip 14. The combined axial height of housing 30 and head 36 is slightly less than that of core tip 14 so that FIG. 3) when the core tip is seated over the assembly tool with flange 20 of core tip 14 engaging base plate 32, entrance flange 22 of core tip 14 will engage the inwardly rounded upper portion of the outer periphery of head 36.

Four Woodruff-type cutters 38 (FIG. 5) are mounted by bolts 39 in recesses 28 spaced at approximately 90 intervals within housing 30 for pivotal movement in planes parallel to the axis of tool 10 between first positions (FIGS. 1 and 3) in which the radially outward facing cutting surface 43 of each cutter is substantially flush with the outer periphery of housing 30 and second positions (FIG. 4) in which the cutting surface outward facing surface 48 thereof. A drilled recess 50 is provided in the bottom of each segment 44 for engaging, in conjunction with the radially inward-facing periphery of rod 46, a half-round milled slot 52 in a stud 54. Each stud 54 is mounted in a drilled recess 56 extending axially into housing 30 and is secured therein by a bolt 58. An oil hole 41 extends from the top of each segment 44 to the recess 50 therein.

A hardened thrust washer 60 is mounted on a shoulder 62 of shaft 34 adjacent the top of housing 30 in engagement with the bottom surfaces 47 of segments 44. A second washer 64 and a pair of nuts 66, 68 are mounted on shaft 34 above and loosely engaging the top of segments 44.

As shown in FIGS. 1, 3 and 4, operating shaft 34 is axially aligned with and secured to the piston 13 of cylinder 12. A drive plate 72 is mounted on the end of piston 13. Three knockout pins 70 extend from a wear plate mounted on the end of cylinder 12, through holes 73 in drive plate 72 and holes 75 in base plate 32, to directly below the end wall of core 16. The sliding movement of pins 70 through drive plate 72 is limited by a key and slot. A tubular sleeve 74 surrounding a portion of drive shaft 34, and four coil springs 76' mounted in circumferentially spaced recesses, are provided intermediate base plate 32 and drive plate 72.

In operation, core tip 14 is placed on assembly tool 10 with flange 20 adjacent base plate 32 and flange 22 adjacent head 36. Core 16 is moved to a position adjacent and axially aligned with the coaxial tip and tool. A valve (not shown) is actuated, supplying air under pressure to cylinder 12 and moving piston 13, and the assembly tool 10 mounted thereon, upward, forcing tip 14 into core 16 and reinforcing flange 22 into engagement with the axially-forcing end of the core. Springs 76 exert a force greater than that required to insert the tip and insure that drive shaft 34 does not move within and relative to housing 30 until the core tip (FIG. 3) is fully inserted into core 16, with flange 20 of the tip engaging the end of the core.

After the core tip has been fully inserted, continued movement of piston 13 overcomes the force of springs 76 and moves drive shaft 32 upwardly within and relative to housing 30 thereby pivoting cutters 38 and head segments 44 into the position shown in FIG. 4. The distance shaft 32 is permitted to move within the housing is limited by sleeve 74, the opposite ends of which, as shown in FIG. 4, engage drive plate 72 and base plate 32 when the desired limit of pivotal movement of the cutters and head segments has been reached. Further piston movement would drive theentire tool upward, crushing core 16. Cylinder 12 is therefore designed to produce less force than would be required for any such crushing and piston movement automatically stops when the upper end of sleeve 72 comes into contact with the bottom of base plate 32.

As shown, the upward movement of shaft 34 within housing 30 moves the inner ends 40 of cutters 38 upwardly, pivoting cutters 38 about bolts 39. The cutting surface 43 of each cutter forced radially outwardly through the adjacent portion of wall 18 of core tip 14, thereby shearing a total of four V-shaped spurs 80 from wall 18 and forcing the spurs outwardly into core 16.

Shaft 34 also moves thrust washer 60 upwardly, pivoting segments 44 of head 36 about the axes of the slots 52 of the studs 54 securing the segments to housing 30 and moving the portions of outer surface 48 of the segments above the slot axes radially outwardly until the diameter of radially outermost portions of surfaces 48 is at least as great as the inside diameter of core 16. As surfaces 48 engage entrance flange 22 of core tip 14, the pivotal movement of head segments 44 expands flange 22 until its inner diameter is equal to or greater than the inside diameter of wall 18 of core tip 14. Preferably, the maximum diameter portions of segment 44 engage the upper axial end portion of flange 22 so that the flange is inverted, forming (FIG. 4) an outwardly flared flange, extending into core 16.

After spurs 80 have been driven into core 16 and flange 22 expanded, the air flow into cylinder 12 is reversed, moving piston 12 downwardly, thereby retracting cutters 38 and head segments 44 and drawing tool axially out of core tip 14, which remains fixed in position within core 16. The upper ends of knockout pins 70 engage the lower end of .core 16 and tip 14 and assist in disengaging the tool from the core.

Other embodiments of the invention within the scope of the following claims will occur to those skilled in the an.

I claim:

1. The method of assembling within tubular cores, tubular core tips of the type having a cylindrical wall and, at one axial end thereof, a radially-inwardly extending entrance flange,

v said method including the steps of:

introducing said core tip, said one axial end first, into said core coaxial therewith;

simultaneously expanding a plurality of circumferentially spaced portions of said entrance flange radially outwardly into the cylindrical wall of said core; and, simultaneously with said expanding,

shearing a plurality of portions of the cylindrical wall of said core tip and forcing said portions radially outwardly into said cylindrical wall of said core.

2. The method of claim 1 wherein said tip includes a radially-outwardly extending flange axially spaced from said one axial end and including the step of introducing said tip into said core until said outwardly extending flange engages an end surface of said core prior to expanding said entrance flange and shearing said portions.

3. The method of claim 1 including the step of forcing said outwardly-extending flange against said end surface during said expanding of said entrance flange and said shearing and forcing of said portions.

4. The method-of claim 1 wherein said portions are regulady-circumferentially spaced.

5. The method of claim 4 wherein said portions are spaced at substantially intervals.

6. The method of claim 2 wherein said core tip includes a key having sides extending radially outwardly from said cylindrical wall of said tip and axially from said outwardly extending flange of said tip, said core includes adjacent said axial end thereof a keyway for receiving said key, and including the step of inserting said tip into said core until said key is positioned within said keyway prior to expanding said entrance flange and shearing said portions.

7. The method of claim 6 including the step of forcing said outwardly-extending flange against said end surface during said expansion of said entrance flange and said shearing and forcing of said portions, and wherein said portions are regulady-circumferentially spaced.

8. The method of claim 1 wherein substantially the entire circumference of said entrance flange is expanded radially outwardly into said cylindrical wall simultaneously with said shearing and forcing of said portions.--;

9. The method of claim 8 wherein said tip includes a radially-outwardly extending flange axially spaced from said one axial end and including the steps of introducing said tip into said core until said outwardly extending flange engages an end surface of said core prior to expanding said entrance flange and shearing said portions, and forcing said outwardly-extending flange against said end surface during said expanding of said entrance flange and said shearing and forcing of said portions.--; and, v

10. The method of claim 9 wherein said core tip includes a .key having sides extending radially outwardly from said cylindrical wall of said tip and axially from said outwardly-extending flange of said tip, said core includes adjacent said axial end thereqfa keyway for receiving said key, and including the step of positioning said key within said keyway prior to expanding said entrance flange and shearing said portions. 

1. The method of assembling within tubular cores, tubular core tips of the type having a cylindrical wall and, at one axial end thereof, a radially-inwardly extending entrance flange, said method including the steps of: introducing said core tip, said one axial end first, into said core coaxial therewith; simultaneously expanding a plurality of circumferentially spaced portions of said entrance flange radially outwardly into the cylindrical wall of said core; and, simultaneously with said expanding, shearing a plurality of portions of the cylindrical wall of said core tip and forcing said portions radially outwardly into said cylindrical wall of said core.
 2. The method of claim 1 wherein said tip includes a radially-outwardly extending flange axially spaced from said one axial end and including the step of introducing said tip into said core until said outwardly extending flange engages an end surface of said core prior to expanding said entrance flange and shearing said portions.
 3. The method of claim 1 including the step of forcing said outwardly-extending flange against said end surface during said expanding of said entrance flange and said shearing and forcing of said portions.
 4. The method of claim 1 wherein said portions are regularly-circumferentially spaced.
 5. The method of claim 4 wherein said portions are spaced at substantially 90* intervals.
 6. The method of claim 2 wherein said core tip includes a key having sides extending radially outwardly from said cylindrical wall of said tip and axially from said outwardly-extending flange of said tip, said core includes adjacent said axial end thereof a keyway for receiving said key, and including the step of inserting said tip into said core until said key is positioned within said keyway prior to expanding said entrance flange and shearing said portions.
 7. The method of claim 6 including the step of forcing said outwardly-extending flange against said end surface during said expansion of said entrance flange and said shearing and forcing of said portions, and wherein said portions are regularly-circumferentially spaced.
 8. The method of claim 1 wherein substantially the entire circumference of said entrance flange is expanded radially outwardly into said cylindrical wall simultaneously with said shearing and forcing of said portions.--;
 9. The method of claim 8 wherein said tip includes a radially-outwardly extending flange axially spaced from said one axial end and including the steps of introducing said tip into said core until said outwardly extending flange engages an end surface of said core prior to expanding said entrance flange and shearing said portions, and forcing said outwardly-extending flange against said end surface during said expanding of said entrance flange and said shearing and forcing of said portions.--; and,
 10. The method of claim 9 wherein said core tip includes a key having sides extending radially outwardly from said cylindrical wall of said tip and axially from said outwardly-extending flange of said tip, said core includes adjacent said axial end thereof a keyway for receiving said key, and including the step of positioning said key within said keyway prior to expanding said entrance flange and shearing said portions. 